全文获取类型
收费全文 | 498篇 |
免费 | 12篇 |
国内免费 | 9篇 |
专业分类
安全科学 | 38篇 |
废物处理 | 33篇 |
环保管理 | 74篇 |
综合类 | 101篇 |
基础理论 | 91篇 |
污染及防治 | 115篇 |
评价与监测 | 30篇 |
社会与环境 | 30篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 10篇 |
2020年 | 7篇 |
2019年 | 9篇 |
2018年 | 12篇 |
2017年 | 13篇 |
2016年 | 16篇 |
2015年 | 9篇 |
2014年 | 20篇 |
2013年 | 55篇 |
2012年 | 15篇 |
2011年 | 38篇 |
2010年 | 20篇 |
2009年 | 23篇 |
2008年 | 29篇 |
2007年 | 30篇 |
2006年 | 30篇 |
2005年 | 21篇 |
2004年 | 19篇 |
2003年 | 23篇 |
2002年 | 18篇 |
2001年 | 5篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1992年 | 5篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1983年 | 6篇 |
1982年 | 4篇 |
1981年 | 6篇 |
1980年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1973年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1961年 | 2篇 |
1957年 | 1篇 |
1956年 | 2篇 |
1955年 | 3篇 |
1949年 | 1篇 |
1947年 | 1篇 |
排序方式: 共有519条查询结果,搜索用时 15 毫秒
101.
102.
Franco Andreone Gonçalo M. Rosa Jean Noël Angelica Crottini Miguel Vences Christopher J. Raxworthy 《Die Naturwissenschaften》2010,97(6):525-543
We describe a new mantelline frog of the genus Blommersia found in rainforest in North East Madagascar, from the protected areas of Ambatovaky, Betampona, Masoala, and Zahamena. Blommersia angolafa n.sp. is a small frog, with a body size of 17–21 mm, expanded finger and toe tips, and colouration ranging from yellow to
dark brown, with pale-bluish spots on the flanks and light tips of fingers and toes. A peculiar aspect characterising this
new species is its novel life history and reproductive mode. Both sexes live and breed in a phytotelmic habitat of water accumulated
within fallen prophylls and fallen leaf sheaths of at least three species of Dypsis palms. Within these phytotelmata, egg laying and complete larval development occur. Thus, B. angolafa n.sp. represents a new evolutionary lineage of Malagasy frogs in which phytotelmy is known. Up to now, reproduction in phytotelmata
in Malagasy frogs has been reported for many cophyline microhylids, most species of Guibemantis, Mantella laevigata, and possibly in a still-undescribed species belonging to the genus Spinomantis. We consider the reproductive mode of B. angolafa as a derived character, having evolved from the more typical reproduction in lentic water bodies. The general scarcity of
lentic habitats in Malagasy rainforests may have provided the conditions that favoured the evolution of this phytotelmic breeding
strategy. The new species, being specialised to a habitat represented by a few selected Dypsis species, potentially suffers the selective exploitation of these palms. 相似文献
103.
The aim of this study was to investigate the effect of relative humidity (RH) and temperature on norovirus (NoV) persistence
as infectious particles on food-contact surfaces such as stainless steel and polyvinyl chloride (PVC). For this purpose, a
new method combining enzymatic digestion with molecular beacon-based NASBA targeting the ORF1-ORF2 domain was developed to
discriminate between infectious and noninfectious NoV. Stainless steel and PVC disks were contaminated with known amounts
of human NoV and kept for 56 days at 7 and 20°C at high (86% ± 4%) and low (30% ± 10%) RH. NoV retained its putative infectivity
for 56 days on PVC and for 49 days on stainless steel at 7°C and for 7 and 28 days, respectively, at low and high RH at 20°C
on both tested surfaces. These results confirm that NoV persists in an infective state on inert surfaces for long periods
of time and consequently may cause illness. The new molecular approach to detecting infectious NoV on inert surfaces may provide
valuable information for evaluating environmental surface decontamination strategies. 相似文献
104.
The purpose of this paper was to contribute to understanding of the crucial role of emotion in work motivation by testing a conceptual model developed by Seo, Barrett, and Bartunek (2004) that predicted the impacts of core affect on three behavioral outcomes of work motivation, generative-defensive orientation, effort, and persistence. We tested the model using an Internet-based investment simulation combined with an experience sampling procedure. Consistent with the predictions of the model, pleasantness was positively related to all three of the predicted indices. For the most part, these effects occurred indirectly via its relationships with expectancy, valence, and progress judgment components. Also as predicted by the model, activation was directly and positively related to effort. 相似文献
105.
Maity JP Nath B Kar S Chen CY Banerjee S Jean JS Liu MY Centeno JA Bhattacharya P Chang CL Santra SC 《Environmental geochemistry and health》2012,34(5):563-574
Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7?% of the sampled tube wells contain As concentrations above 10?μg/L, while 57.7?% contain As concentrations above 50?μg/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99?μg/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region. 相似文献
106.
Marianne Robert Laurent Dagorn Jean Louis Deneubourg David Itano Kim Holland 《Marine Biology》2012,159(4):907-914
Several lines of evidence indicate that aggregations of yellowfin tuna associated with floating objects are more frequently
composed of small animals than larger ones. Also, the diet of small yellowfin tuna caught at anchored fish aggregating devices
(FADs) around Oahu, Hawaii, was found to shift quite rapidly when these fish reached approximately 50 cm FL. In order to test
for ontogenetic changes in aggregation behavior, we tagged and released two distinct size classes of yellowfin tuna in an
array of anchored FADs around Oahu, Hawaii. Twenty-four yellowfin tuna 30–39 cm FL and 16 yellowfin tuna 63–83 cm FL were
tagged with acoustic transmitters and released near anchored FADs equipped with automated acoustic receivers. Fish in the
smaller size class stayed about 2.5 times longer at individual FADs than the larger fish (mean 4.05 days vs. 1.65 days) and
displayed larger horizontal movements within the array. However, the durations of unassociated phases, residence times in
the entire FAD array, percentage of time spent associated with FADs and numbers of movements between FADs did not show any
difference between the two size groups. The observed size-dependent behavior is discussed in terms of physiological abilities,
diet segregation and anti-predator behavior. 相似文献
107.
Special needs hurricane shelters and the ageing population: development of a methodology and a case study application
下载免费PDF全文
![点击此处可从《Disasters》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mark W. Horner Eren Erman Ozguven Jean Michael Marcelin Ayberk Kocatepe 《Disasters》2018,42(1):169-186
Recent experience of hurricanes, particularly in the southeast United States, has heightened awareness of the multifaceted nature of and the challenges to effective disaster relief planning. One key element of this planning is providing adequate shelter at secure locations for people who evacuate. Some of these individuals will have ‘special needs’, yet there is little research on the relationship with shelter space. This study designed a geographic information systems‐based network optimisation methodology for the siting of special needs hurricane relief shelters, with a focus on the transportation component. It sought to find new locations for shelters that maximise accessibility by vulnerable populations, given capacity constraints, concentrating on the ageing population. The framework was implemented in a medium‐sized metropolitan statistical area in the state of Florida where data suggest a possible deficit in special needs shelter space. The study analysed options for increasing special needs shelter capacity, while considering potential uncertainties in transportation network availability. 相似文献
108.
在线富集HTLC/MS/MS分析环境水资源中多种抗生素 总被引:2,自引:0,他引:2
<正>人们日益关注环境水资源中抗生素的存在情况.这迫使环境和政府实验室开发新的液相色谱/质谱(LC/MS)方法,以监测水资源中抗生素的存在状况.然而,环境水资源中含有的抗生素通常是很痕量的,往往需要大量的水样进行富集和净化.在液相色谱/质谱(LC/MS)分析之前,需要对大约100—1000ml水样进行富集和清理,以达到被测物质的检测限。 相似文献
109.
Ornamental comb colour predicts T-cell-mediated immunity in male red grouse <Emphasis Type="Italic">Lagopus lagopus scoticus</Emphasis> 总被引:1,自引:1,他引:0
Mougeot F 《Die Naturwissenschaften》2008,95(2):125-132
Sexual ornaments might reliably indicate the ability to cope with parasites and diseases, and a better ability to mount a primary inflammatory response to a novel challenge. Carotenoid-based ornaments are amongst the commonest sexual signals of birds and often influence mate choice. Because carotenoids are immuno-stimulants, signallers may trade-off allocating these to ornamental colouration or using them for immune responses, so carotenoid-based ornaments might be particularly useful as honest indicators of immuno-compentence. Tetraonid birds, such as the red grouse Lagopus lagopus scoticus, exhibit supra-orbital yellow-red combs, a conspicuous ornament which functions in intra- and inter-sexual selection. The colour of combs is due to epidermal pigmentation by carotenoids, while their size is testosterone-dependent. In this study, I investigated whether comb characteristics, and in particular, comb colour, indicated immuno-competence in free-living male red grouse. I assessed T-cell-mediated immunity using a standardised challenge with phytohaemagglutinin. Red grouse combs reflect in the red and in the ultraviolet spectrum of light, which is not visible to humans but that grouse most likely see, so I measured comb colour across the whole bird visible spectrum (300-700 nm) using a reflectance spectrometer. I found that males with bigger and redder combs, but with less ultraviolet reflectance, had greater T-cell-mediated immune response. Comb colour predicted T-cell-mediated immune response better than comb size, indicating that the carotenoid-based colouration of this ornament might reliably signal this aspect of male quality. 相似文献
110.
Oram JJ McKee LJ Werme CE Connor MS Oros DR Grace R Rodigari F 《Environment international》2008,34(8):1137-1147
A mass budget of polybrominated diphenyl ethers (PBDEs) in San Francisco Bay is developed as a first step towards understanding the local sources and transport processes controlling PBDE fate in a highly urbanized estuary. Extensive monitoring of PBDEs in estuarine water and sediment, freshwater tributaries, air, and wastewater effluents and sludges were integrated with a mass budget model to provide a synthetic view of these emerging contaminants. The Bay inventories of BDE 47 and BDE 209 in 2006 were estimated to be 33+/-3 kg and 153+/-45 kg, respectively. Empirically derived estimates of annual inputs of BDE 47 and BDE 209 from all quantifiable external sources ranged from 11 to 28 kg/y and 22 to 24 kg/y, respectively. BDE 47 loads were dominated by wastewater while runoff from local tributaries represented the largest contributor to BDE 209 loads. Model results suggest the Bay PBDE inventory is highly sensitive to changes in external loads, with degradation and outflow being the major processes governing PBDE fate. The mass budget presented provides a framework for integrating future monitoring and modeling efforts. 相似文献